Bone marrow transplantation improves hepatic fibrosis in Abcb4-/- mice via Th1 response and matrix metalloproteinase activity
Bone marrow transplantation improves hepatic fibrosis in Abcb4-/- mice via Th1 response and matrix metalloproteinase activity
复制标题
DOI：
10.1136/gutjnl-2011-300608
复制
发表时间：
2012-06-01
期刊：
影响因子：
24.5
通讯作者：
Roeb, Elke
中科院分区：
文献类型：
--
作者：
Roderfeld, Martin;Rath, Timo;Roeb, Elke
目的关于骨髓源性细胞在肝纤维化中作用的报道相互矛盾。最近在Abcb4(-/-)小鼠骨髓移植(BM-TX)后10周发现纤维化受损，但炎症增加。假设BM-TX可能通过改变免疫和基质重建过程导致肝再生而具有长期治疗潜力。方法将GFP+供体小鼠(异基因TX)或Abcb4(-/-)小鼠(同基因TX)接受致死性照射后，经尾静脉注射BM-TX。在TX后2周、10周和20周进行读数。对肝脏完整性进行血清学和组织学评估。用实时定量聚合酶链式反应、酶谱和免疫组织化学方法分析肝纤维化、辅助性T细胞(Th)应答、炎症反应、移植物抗宿主病和纤溶的替代指标。结果BM-TX移植20周后，肝组织分级和分期明显改善。相反，BM-TX炎症分级后2周，炎症细胞标志物及其相关趋化因子及其受体的表达增加，随后下降。同时，CD8+/GFP+供者来源的T细胞在BM-TX后2周进入肝脏。BM-TX后2周和10周Th1细胞因子干扰素-γ水平升高，而Th2相关白介素13水平无变化。BM-TX后20周，基质金属蛋白酶MMP2、MMP7、MMP9和MMP13基因表达一过性上调，MMP9蛋白表达持续升高，纤维化区明胶酶活性增强。中性粒细胞是基质金属蛋白酶-9的主要来源。结论BM-TX可诱导抗肝纤维化的Th1反应，并伴有一过性炎症反应，进而上调基质金属蛋白酶活性。抗纤维化的Th极化和持续的蛋白分解活性，尤其是基质金属蛋白酶-9，可能是长期改善肝纤维化的原因。
Objective Reports on the effects of bone marrow-derived cells on hepatic fibrosis are contradictory. Impaired fibrosis but increased inflammation has recently been demonstrated 10 weeks after bone marrow transplantation (BM-Tx) in Abcb4(-/-) mice. It is hypothesised that BM-Tx might have long-term therapeutic potential by altering the immunological and matrix remodelling processes leading to hepatic regeneration.Methods After lethal irradiation of recipient mice, BM cells from GFP+ donor mice (allogeneic Tx) or Abcb4(-/-) mice (syngeneic Tx) were transplanted via tail vein injection. Readouts were performed 2, 10 and 20 weeks after Tx. Liver integrity was assessed serologically and histologically. Surrogate markers for fibrogenesis, T helper (Th) response, inflammation, graft-versus-host disease and fibrolysis were analysed by quantitative real-time PCR, zymography and immunohistology.Results 20 weeks after syngeneic and allogeneic BM-Tx, hepatic grading and staging were significantly improved. In contrast, 2 weeks after BM-Tx inflammatory grading, expression of inflammatory cell markers and associated chemokines and their receptors were increased and subsequently declined. In parallel, CD8+/GFP+ donor-derived T cells infiltrated the liver 2 weeks after BM-Tx. The Th1 cyokine interferon gamma was increased 2 and 10 weeks after BM-Tx whereas the Th2 associated interleukin 13 was not altered. The gene expression of matrix metalloproteinases MMP-2, MMP-7, MMP-9 and MMP-13 was transiently upregulated and MMP-9 protein remained elevated 20 weeks after BM-Tx with enhanced gelatinase activity located within the fibrotic areas. Neutrophils were identified as major sources of MMP-9.Conclusion These results show that BM-Tx causes an antifibrotic Th1 response combined with transient inflammatory effects and subsequently upregulated MMP activity. Antifibrotic Th polarisation and prolonged proteolytic activity, especially of MMP-9, might be responsible for long-term amelioration of hepatic fibrosis.